Veneer composers are machines adapted to assemble random width pieces of veneer into a continuous ribbon of veneer. The continuous ribbon may be further cut into sheets of a desired length, joined, and layered as necessary to make engineered lumber such as Laminated Veneer Lumber (LVL) and plywood.
A typical composer may include a feed station where an operator selects and feeds veneer sheets to be processed by the composer. The veneer pieces may be of varying widths and have non-squared edges and/or defect regions that require trimming prior to the veneer pieces being formed into a continuous ribbon. Traveling on a conveyor through the composer, a clipping station clips the leading and trailing edges of each veneer piece to produce parallel and squared edges. Defects in the veneer pieces are also clipped to entirely remove the defect in a particular piece. The clipping of the leading and trailing edges, as well as removal of the entire defect, not only is a source of great waste, but it also wastes time and increases the number of operations required by the clipper.
Once the edges and defects are clipped, the individual pieces are crowded edge-to-edge against each other at a crowding station. The crowding station is generally a conveyor that is traveling at a rate significantly less than the material flow rate of the individual veneer pieces coming from the clipping station. This difference in speed causes the leading edge of a trailing piece to ram into or crowd with the trailing edge of a leading piece to ensure there are no gaps therebetween. Crowding is acceptable for some wood species, but not others. Woods like Eucalyptus are susceptible to bunching when run through a crowding station, which results in machine downtime. Also, crowding the edges of adjacent pieces may cause one edge to rise above and overlap the adjacent piece. Such overlapping causes manufacturing problems when the sized veneer sheets are layered, and can result in unacceptable weaknesses.
To hold the crowded pieces of veneer together, adhesive impregnated strings are typically bonded to one or both sides of the veneer pieces, thereby forming a continuous ribbon of veneer. This continuous ribbon is then passed through another clipping station where sheets of a desired length are clipped for further processing into engineered wood.
Improving on the composers described above is necessary in order to reduce the amount of waste that is generated. Further, improvements are needed to improve the continuity of the flow rate of material through the composer in order to increase the efficiency and effectiveness of the machine, particularly with materials that tend to require more delicate handling.